Collet for lathes and other machines.



G. P. SGHULTIS. OOLLET FOR LATHES AND OTHER MACHINES. APPLICATION FILED MAR.5,1910.

1,076,71 O. Patented Oct. 28, 1913.

3 sHEBTS-SHEET 1.

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C. P; SCHULTIS. COLLET FOR LATHES AND OTHER MACHINES.

APPLICATION FILED MAR.5, 1910.

1,076,710. Patented 0ct.28,1913.

3 SHEETS-SHEET 2.

Fig. 3.

\ Pi g. 4.

C. F. SCHULTIS. COLLET FOR LATHES AND OTHER MACHINES.

APPLICATION FILED MAR. 5, 1910.

1,076,710; I Patented Oct. 28,1913.

' 7 3 EHEETS-SHEET 3.

23CDO INVENTOR CZarZss BY #441 LAM ATTYS STATES PATENT OFFICE.

CHARLES r. :s en'nnras,

or CLEW'TE-Ldilfifi), onto.

COLLlE'I FOE LATHES AND OTHER MACHINES.

i .Specifioatioh of Letters Patent.

Patented Oct. 28, 1913.

Application and March 5, 1-910. serialize. 547,496.

chines, and consists particularly in an improvement upon the construction or style of collet shown and claimed in my application Ser. No. 461,710, of Nov. 9, 1908.

In the accompanying drawings, Figure 1 is a sectional elevation of the entire device taken axially, and Fig. 2 is a front elevation thereof. Fig. 3 is a side elevation partially sectioned, and Fig. i is a cross section on a line corresponding to w--m, Fig. 1. Fig. 5 is a side elevation of a modification of the body of the collet, and Fig. 6 is an edge elevation partially in section of a portion of the hood. Fig, 7 is a sectional clevation of the hood alone. Fig. 8 is a perspective of one of the cam segments. Fig. 9 is a front elevation of the so-called body, and Fig. 10 is an end elevation of the jaw holder, looking from the base outward.

Referring first to the several parts as such and their relative positions and arrangements, B represents the body of the collet adapted to be reinovably engaged upon a drive head or spindle S, or its equivalent, and in this instance has an internal thread 2, shown in Fig. 1 as screwed on the reduced 'hreaded extremity 3 of said head or spindle. 'lhe hood E is sleeved part way over or upon the outer portion of body B against an annular rib or flange 4: thereon and looked rigidly but removably upon said body by means of a clamping ring L. Said ring is threaded upon the reduced and threaded portion 5 of said hood and has an inside flange 6 at its opposite edge hearing against said rib 4c. The foregoing construction locks the said several parts 13, S and E rigidly together for operation, and said hood has serrations h in a portion of its edge, Fig. 3, engaged by teeth on an in.

sort a in said rib l and adapted to prevent rotation. of either part excepting when adjjustments are to be made to set the collet for different sizes of stock, as hereinafter dc scribed.

H represents the so-called jaw supporting head, and J the three several jaws theein. The said head is screwed upon or engaged by the inner end of a tube 'lljvlrich slidably mounted in drive spindle or head S, and supposed to extend inward as to the machine and as common in screw iiiachines so as to be within reach of the operator and is adapted to be pushed forward like a plunger for the operation of said head and the jaws J. In this connection it will be ob served that body I) has radially disposed recesses 7 in its tace, Fig. 9, provided with sockets or depressions 8 and jaw head H, has radially projecting short arms or lugsk at its base adapted to occupy said recesses and also provided with sockets or hores if) of a size to receive spiral springs 12 and constructed to seat said springs in the base of said sockets. The said sockets 10 in arms 72. are directly opposite the sockets 8, and a tiat ring 14 about the base portion of the said jaw supporting head has pins or stems 13 engaged therewith or fixed thereon in this instance and ektending through said springs and holes in the bottoms of sockets 10 into sockets 8, wherein said stems have cotter pins or the like to confine the same operatively. Said ring occupies an otherwise free space in front of the face edge of body B and of suflicient depth to aiiord head H all the room it requires for thrust movement, the springs 12 being compressed when such movement occurs and serving to Withdraw said head when thrust is withdrawn.

In the present views the head H is withdrawn and the jaws J are open their full limit or where they can take the largest stock or work of which this collot is capable. In this connection it is also to be noted that the head H is tapered about its body or jaw sustaining portion and has radial slots occupied by the jaws, as usual. The jaws themselves are shown as correspondingly tapered upon their outer edges while their inner cutting edges come square and straight to the work.

C represents three several cam segments which are disposed in hood E about the jaws and are tapered both lengthwise and transversely of the co'llet, see Figs. 1 and at. Hence a compound cam effect is obtained because theexternal taper of the jaws cooperates with the doubletaper of the cams to thrust the jaws inward when head H is moved axially tor-ward and when hood E is independently rotated. It will of course be understood that the movements of these parts is limited, especially the axial or longitudinal movement of head H which requires only a slight travel to cause effective gripping of the work by the jaws. The rotative movement of hood E may be 90 more or less to adjust the jaws to gripping position on stock from one-eighth to one inch in diameter, more or less. An outer disk D is secured to the outer or face end of said head by screws 16 and which serves to confine the jaws in the head and behind which said jaws are in free sliding position at all times, subject of course to the adjusting mechanism therewith and their own springs 20. The said springs 20 have the novel and original arrangement shown, the same occupying triangular bores 19 through the stock or land between the slots contain ing said jaws and seated at their ends in correspondingly inclined recesses 21 in the sides and inner ends of said jaws. Thus each spring bears against a single jaw at each end, and being arranged at acute angles to the sides of the jaws they exert a constant tension from the working to the retiring position of the jaws which relieves or minimizes binding or frictional engagement between the sides of the jaws and the slots of the head. It follows that they keep the jaws back in engagement with cams G and each spring acts equally on two jaws. Thus said springs equalize each other and all the jaws are pressed backward after release from the work or when adjustments are made.

The segments C are removably fixed in the hood E at their respective ends between the transverse ribs or bars 23, and said ribs or bars form abutting shoulders on their opposite sides for said segments and are secured by rivets or screws 24 through hood E. Said ribs however extend inward only the width of said segments and no farther.

Fig. 5 shows a modification B of head B and is adapted to make internal rather than external connections with a power member corresponding otherwise to spindle or part S.

In use, and assuming that the collet requires adjustment to meet a specific need, the first step is to unscrew clamping ring L sufiiciently to permit disengagement of serrations Z). This effects unlocking of body B and hood E, springs 12 forcing hood E forward in respect to body B. Springs 12 also serve to maintain seating relations between head H and body B. Hood E is now free to be rotated, and if rotation is to the right the several jaws J will be forced inward equal distances by cam segments C until the stock is engaged or until the receptive position of the jaws for a certain sized stock is reached. Hood E. and body 13 are now again locked together by clamping ring L so that positive rotation of all the parts may proceed when, the work is inserted between the jaws. As hereinbefore described, gripping of the work by the jaws is obtained by forcing head H forward which thrusts the jaws against the tapered cam segments, thereby moving the aws radially inward in the right degree. Upon a return or release movement of head H, equalizing springs 20 throw the jaws outward.

\Vhat I claim is:

l. A collet having a jaw head with an externally tapered body and jaws therein correspondingly tapered on their outer edges, in combination with a hood about said parts, a cam segment for each jaw tapered transversely from its outer to its inner edges and between its ends and permanently fixed in said hood, and springs interposed between the inner edges of said segments and the base of said jawholder and adapted to press said holder inward.

2. A collet having a jaw supporting head provided with radially disposed slots for jaws and bores through the stock between said slots at an acute angle to the sides thereof, jaws in said slots having recesses in their-sides and springs in said bores engaged in said recesses said springs bearing against one side of one jaw at one end and against the adjacent side of the adjacent jaw at the other end.

3. An adjustable-collet comprising a lurality of jaws tapered outward on tieir outer edges, a jawholder in which said jaws are mounted correspondingly tapered on its outside, and spiral springs interposed be tween adjacent jaws and bearing against the sides thereof, in combination with a hood and a transversely and longitudinally tapered segment behind each jaw and fixed in said hood behind said jaws.

4.. The combination of the body and hood of a collet separably united, a jaw supporting head therein and radially disposed jaws in said head, springs disposed about the axis of said head bearing at their ends against the sides of adjacent jaws, a. series of separate cam segments fixed in said hood about said jaws, a spring pressed ring interposed between said segments and the base of said head and a disk ring fixed upon the face of said head outside said jaws and adapted to come within the front face of said hood.

In testimony whereof I a'lfix my signature in presence of two witnesses.

CHARLES F. SCHULTIS. lVitnesses:

E. M. FISHER, F. C. MussUN.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

